This inventions relates to an apparatus for transferring heat or cold to food articles and, more particularly, to a novel apparatus particularly adapted for holding previously cooked food articles quite near to a preferred temperature for prolonged time periods, and which can also be employed to initially cook food articles or to complete the cooking of food articles that have been previously partially cooked. In addition, the apparatus can also cool the previously cooked or partially cooked food articles or freeze them.
The novel method of cooking and holding food articles for which the present apparatus is utilized is disclosed in U.S. Pat. Nos. 4,210,675, 4,224,862 and 4,278,697 the contents of which are to be incorporated herein by reference in their entirety.
Briefly, the U.S. Department of Agriculture has long determined that there is considerable danger of spoilage and salmonella (food poisoning bacteria) development in food articles which are held for even short periods of time at temperatures ranging between 40.degree. F. and 145.degree. F. Prior art apparatus utilizing, for example, electrically heated air, steam, etc. have encountered problems in attempting to maintain warm food articles held in the apparatus at temperatures above 140.degree. F. within a temperature range of +5.degree. F. without also causing considerable undesired additional cooking or "overcooking" of them as pointed out in the aforementioned patents. The method comprises storing cooked meat or other food articles in a chamber having closure means intended to be repeatedly and frequently opened and closed, supporting the cooked food articles on support means located within the chamber, forcing a heated liquid heat-transferring medium through radiator means located adjacent to and on opposite sides of the support means, and maintaining the humidity within the chamber above that of the atmosphere outside of the chamber and the temperature above 140.degree. F. and within a temperature range of +5.degree. F. The apparatus disclosed in the aforementioned patents for practicing the aforestated method consisted basically of mounting a plurality of support means in vertical stacked relationship to each other. Each of the support means consisted of a plate to which is secured a serpentine coil for transferring the heated fluid. The coils of each support means are connected in series relationship to the pump and the sump containing the heated liquid. The aforedescribed support means it has been discovered is both inefficient and expensive to manufacture. The support means were not removable and the serial connection of all of the plates with their serpentine coils results in an unacceptably high pressure loss of fluid flowing through the coil and the necessity of using a larger pump. In addition, inefficient heat transfer and poor heat distribution resulted from the prior art design and coil connection. Further, placing the sump and pump on the bottom of the heating chamber inhibits air removal from the circulated fluid. The problems associated with the prior art apparatus are eliminated in the present invention by placing the sump and pump above the vertical stack of food support means.
The support means themselves are also novel in that they are removably held in vertically, spaced-apart relationship on mounting means secured to the side walls of the cabinet. The support means each consist of a plurality of spaced-apart tubular members each having one end thereof connected to a first plenum and the other end connected to a second plenum to form a fluid tight, hollow interior. The tubular members and plenums have a wick on the inside thereof consisting of a metallic screen material and a heat transfer medium in the form of water or volatile fluid partially fills the interior. The spacing between the tubular members permits visual inspection through layers of supports for the presence of food product left beneath the supports and their removability permits cleaning, maintenance and replacement.
The mounting means for the support means are also tubular in shape and each has a fluid inlet and outlet. The inlet and outlet of each mounting means is connected to a header system through which heated or cooled fluid is circulated by means of a pump. The plenums of the support means rest on the mounting means and heat is transferred therebetween by means of conduction.
It is therefore the primary object of the present invention to provide a superior apparatus for thawing, cooking, holding and cooling food articles.
It is another object of the present invention to provide a novel support for pans containing the food articles which is removable yet achieves even heat distribution by means of a novel wick system contained therein.
It is yet another object of the present invention to provide a novel header system for interconnecting a series of support mounting means which ensures an even supply of heating or cooling fluid.
Other objects and advantages of the present invention will become apparent and obvious from a study of the following description and accompanying drawings, which are merely illustrative of the present invention.